This invention relates to a platform and support structure for use in trailers in combination with truck tractors. More particularly, the invention relates to a floor and beam construction for use in such trailers.
Prior art truck trailer support floor and beam constructions comprise a pair of main steel or aluminum I beams running from front to rear of the trailer. The beams have a vertical web and upper and lower flanges. The beams may have different web heights, especially in front of the trailer to accommodate the tractor portion which receives and secures the trailer via a king pin assembly. The trailers which may be 33 feet or more in length comprise a plurality of aluminum or steel I beam cross-members which run transversely of the main beams. The cross beams may include a central cross-beam secured between the two main beams and cantilevered cross-beams secured to the outer side of each of the main beams to form aligned cross-beams. The cross-beams may be welded or bolted to the main beams.
Flooring comprising extruded aluminum or wood planks is secured on top of the cross-beams and the main beams. The extruded aluminum floor may have depressions and ridges therein running from front to rear of the trailer to provide wear surfaces for cargo. A U-shaped aluminum or steel side rail is secured to the sides of the trailer at the ends of the aluminum cross-members on each side of the trailer. An aluminum or steel stake pocket and rub rail member is secured exterior the aluminum side rails. The side rails extend from front to rear of the platform formed by the cross-beams and the aluminum floor. The side rails each may have one leg which is coextensive with the bottom flange of an exterior-most aluminum cross-member and a second leg member which is flush with the top surface of the extruded aluminum floor. A steel arrangement differs from this.
The aluminum side rails are welded or otherwise secured to the aluminum cross-beams and floor to form a finished floor support structure. A plurality of spaced aluminum bracing tubes are connected between the main I-beams adjacent to the bottom flanges thereof along the length of the trailer. A set of spaced diagonally-arrowed aluminum brace tubes are connected between the exterior sides of the main-beam lower flanges and the underside of the exterior ends of the aluminum cross-members to provide torsional resistance to the platform structure.
The above-described platform is a combination of steel and aluminum and is relatively heavy. For example, the main steel beams extend from the region adjacent to the upper load-bearing surface of the aluminum floor to the base bottom flange of the beam and may comprise, for example, 7 gauge steel at the center web. Since two of these beams are employed, they represent considerable portion of the entire weight of the trailer platform structure.